Fluid-operated reciprocating machine tool



Jan. 22, 1929.

J. L. HOLMAN ET AL FLUID OPERATED RECIPROCATING MACHINE TOOL Original Filed May 9, 1925 Patented Jan. 22, 1929.

burrs!) STATES PATENT orrics.

JOHN LEONARD HOLMAN AND ARTHUR TREVE HOLMAN, OF GAMBOR-NE, ENGLAND, ASSIGNORS TO HOLMAN BROTHERS LIIVIEITELD, OE" v(JAMBQIRFNE, CORN'WALL, ENG- LAND, A BRITISH COMPANY.

FLUID-OPERATED RECIPROCATING MACHINE TOOL.

Original application filed May 9, 1925, Serial No. 29,108 and in Great Britain February 24, 1925.

Divided and this application filed July 13, 1926. Serial No. 122,1 31.

This invention relates to fluid-operated reciprocating imichine-iools, such for examgle as pneumatic hai'nmers for riveting, c i1. iug, caulking and such like operations, of the kind wherein a handle member is detachablv attached to a body portion containing the working cylinder for the reciprocating piston, which cylinder extends into a recess in the handle member, and the inven tion has particular reference to the construction and arrangement of the handle of the tool, one object being to enable the handle member to be manufactured at a low cost, and another being to provide an improved joint between the handle member and body portion.

According to the invention these objects are attained by providing that the said rcc-iss constitutes by itself. or by means only c 1. a liner within it, a. portion of the working o .nder, and the said fluid-tight joint is con- .l s-stituted by a joint ring which is malleable or c mpressible interposed. between the opposed end faces of the handle member and body portion, whereby a close and fluid-tight joint between these parts can be obtained even it the opposed end faces are of such a nature that when placed directly facc-to-fac'e a thin -tight joint would not result.

In order that the invention may be more clearly understood one preferred construction of ri voting hammer will now be described by way of example only with the aid of the accompanying drawings, in. which igure 1 a longitudinal central section through the hammer;

figure is a section on the line 2-2 of Figure 1; and

Figure 3 illustrates partly in outside elevatioii and partly in section a modification ot' the invention.

Like reference numerals indicate like parts in the several figures.

Referring first of all. to Figures 1 and 2 the handle 10 is provided with the usual 'gger-controlled throttle valve 11, the trigr of which is shown at 12. The valve 11 ii'ts driving fluid, for example, compressed air, from the main supply conduit 13 by way 01 a. port 1 1 to an annular recess formed in the body of the handle. A liner 16 constitutes the inner wall of the recess 15 and also serves as an extension of the working cylinder 24 of the tool.

The annular recess 115 communicates with a pair of ports 17 which coincide with sin1- ilar ports in a joint ring 18 and in the cylinder casing 19. I

The joint ring is preferably composed of fibre or other packing or jointing material which will enable a close and fluid-tight joint to be obtained between it and the handle on one side and the cylinder casing 19 on the other side. The material may be such as to be slightly compressible so that the parts on the other side can become slightly embedded in it. The construction, arrangement and operation of other parts of the tool are described in co-pending application Serial No. 29,108, tiled 9th May, 1925, from which this application has been divided out, and. as, except for the handle and joint ring, the other portions of the tool form no part of the present invention they will not be described herein except to point out that in the joint ring 18 there is a port 118 communicating as shown, directly with the end of the valve chamber 22 and with another port 38 by which driving fluid is led into the rear end of the working cylinder 2 1.

In a modified form of the invention as illustrated in Pi nic 3, the handle 10 is of hooked or open form and the fluid supply is taken direct from a passage 1 10 in the handle through the port in the joint ring 18 to the valve chamber 22 without passing through an annular passage round a cylinderentension such as 116. In this case the extension 116 is not hushed as in the example illustrated in Figure 1.

Referring to the joint ring it is to be observed that it may be of any preferred material not necessarily fibre referred to hereinbetore. For instance it may be @0111- posed of an asbestos graphite composition or it may be formed of lead or even of other material which is not necessarily compressible.

The provision of such a joint ring has a considerable advantage in that the machining of the faces of the two parts between which it is disposed need not be carried out with such accuracy as would be necessary if the two parts were held together face to face so as to glve the required fiu1d-t1ghtness to the joint between them. Also, when the joint ring becomes damaged or Worn so that it is no longer efficiently serviceable, it may be readily replaced, and its replacement is a matter of small expense only. Another advantage is that the faces of the joint ring, when the latter is made of material into which the parts can be somewhat embedded, require no machining and the joint ring can be stamped, moulded or otherwise formed according to the nature of the material employed.

We claim l. A fluid-operated reciprocating machinetool comprising in combination a body portion containing one part of a working cylinder for a reciprocating piston, a handle member detachably attached to said body portion and having a recess, a liner in the latter dividing the recess into an annular fluidsupply passage, and a chamber that is surrounded by said passage and constitutes another part of the working cylinder, a valve chest carried by the body portion and opening through a port in the end face thereof adjacent the handle member, and a joint ring composed of yielding material interposed between the opposed end faces of said body portion and handle member, which joint ring has ports for permitting communication between said parts of the working cylinder, and between the valve chest and the working cylinder, and between the said annular passage and the valve chest, substantially as described.

2. A fluidoperated reciprocating machinetool comprising in combination a body portion containing one part of'a working cylinder for a reciprocating piston, a handle member detachably attached to said body portion and having a recess, a liner in the latter dividing the recess into an annular fluid-supply passage, and a chamber that is surrounded by said passage and constitutes another part of the working cylinder, a valve chamber in said body portion, a reciprocating valve in said chamber, and a joint ring composed of. yielding material interposed between opposed end faces of said body portion and handle memher and constituting one end wall of the valve chamber, substantially as described.

In testimony whereof we have signed our names to this specification.

JOHN LEONARD HOLMAN. ARTHUR TREVE HOLMAN. 

